Cocaine Use Slows Fat Metabolism, Makes Recovery Even More Difficult

Cocaine has long been thought to prevent weight gain in regular users by acting as an appetite suppressant, but new research from a team of UK scientists has found that the illegal drug actually has a metabolic effect that prevents the body from storing fat.

While that may be seen as a desirable side-effect, these metabolic changes can result in dramatic weight gain during recovery – making the rehabilitation process even more distressing. The study findings contradict the notion that weight gain during recovery was a result of patients replacing drug abuse with overeating.

“Notable weight gain following cocaine abstinence is not only a source of major personal suffering but also has profound implications for health and recovery,” said study co-author Karen Ersche, a behavioral scientist at the University of Cambridge. “Intervention at a sufficiently early stage could have the potential to prevent weight gain during recovery, thereby reducing personal suffering and improving the chances of recovery.”

In the study, which was published in the journal Appetite, the UK researchers recruited 60 men, half of whom were regular users of cocaine. The team evaluated participants’ body composition, eating behaviors and levels of leptin, an appetite and energy use hormone.

The British scientists found that cocaine users in the study tended to have a preference for high-fat, high-carbohydrate foods and bouts of uncontrolled eating. However these men often had significantly less body fat compared to the control group. Many of the regular users even experienced significant weight loss.

Regular users also showed lower levels of leptin that were related to the duration of cocaine use. The findings were unusual in that lower leptin levels and a high-fat diet typically lead to weight gain. The researchers said these findings indicate that users’ overeating habits pre-date any recovery process that often results in weight gain.

“We were surprised how little body fat the cocaine users had in light of their reported consumption of fatty food,” Ersche said. “It seems that regular cocaine abuse directly interferes with metabolic processes and thereby reduces body fat. This imbalance between fat intake and fat storage may also explain why these individuals gain so much weight when they stop using cocaine.”

“For most people weight gain is unpleasant but for people in recovery, who can gain several (pounds), this weight gain goes far beyond an aesthetic concern but involves both psychological and physiological problems,” she added. “The stress caused by this conspicuous body change can also contribute to relapse. It is therefore important that we better understand the effects of cocaine on eating behavior and body weight to best support drug users on their road to recovery.”

Hugh Perry, chair of the Neurosciences and Mental Health Board at the Medical Research Council that funded the study, said the study helps to inform the treatment process and could benefit individuals in the longer term.

“This research has clear implications for our understanding of how the body processes fat during chronic cocaine dependency and also how the body adjusts during withdrawal and recovery from dependency,” he said.